[Android] How can I know if an app has been purchased or downloaded?

Question

Android

For example, they downloaded it from w3bsit3-dns.com, copied the APK from another device (and another Google account).
I am learning Android LVL (License Verification Library). I just don’t understand, does it check the license of the account or device?

Answer 1

Through Google Play. Expand your question in more detail.

Answer 2

If the application is purchased, then on the account of the person who bought it, there is a jackdaw conditionally - "application purchased". In the application, using Android LVL, you can ask "does the current account have such a checkbox on the device." If not, the application is most likely downloaded from a third-party site.